Sheet metal nibbler construction



March 25, 1958 1. J. YERMISH 2,327,695

SHEET METAL NIBBLER CONSTRUCTION Filed July 50, 1957 43 i 44 49 j M- 3 2 5 6O '2 45 52 I 4 46 4 35 I 9 45 3/ "I, f 53 5a 5F A 354 "nun". 9 I .57 i5 I 34 I G fimmfiz 33 7 5o I/I/ 49 3 2 INVENTOR.

ISQAEk Q. YERwus Ufiifc tats aszasss Patented Mar. 25, 1958 ice SHEET METAL NIBBLER (IUNSTRUiJTlQN Israel'J. Yermish, Philadelphia, Pa., assignor to Fenway Machine Company, Inc., Philadelphia, Pin, a corpora tion of Pennsylvania Application July 39, 1957, Serial No. 675,112

Claims. (Cl. 30-228) This invention relates generally to metal cutting tools and more particularly to an improved construction of portable, hand held sheet metal cutting tools of the nibbler type.

A principal object of the present invention is to provide an improved mounting for the means that actuates the reciprocating punch of the tool.

Another principal object of the present invention is to provide such a tool having the punch actuating means of aforesaid extending through the upper end of a ram and over the upper end of a punch that depends from the lower end of the ram, and having means adjustably fixing the punch to the ram and readily accessible and operable through the casing of the tool and the punch actuating means aforesaid.

Other objects and advantages of the present invention will appear more fully hereinafter, it being understood that the invention consists substantially in the construction, combination, location and relative arrangement of parts, all as described in the accompanying drawing and as finally pointed out in the appended claims.

In the accompanying drawings:

Figure l is a view looking at one side of a tool constructed in accordance with and embodying the principles of the present invention, a portion being in elevation and a portion in vertical section.

Figure 2 is a section on line 2-2 of Figure l.

Figure-3 is a section on line 33 of Figure Figure 4 is a section on line 44 of Figure Referring to the drawing, the nibbler tool constructed in accordance with and embodying the principles of the present invention is provided with a body designated a head designated 11 that is mounted upon the body in axial extension thereof, and a nose designated 12 that extends laterally from the head 11. Normally the body and head 11 extend horizontally, and the nose 12 depends therefrom.

The body 10 houses an electric motor (not shown) that is supplied with power through the medium of a cable 13,- the electric motor being controlled by the operator through finger pressure applied to a switch control lever 14 that is mounted upon a handle 15. The body it and head 11 are internally provided with means, presently to be described, for translating the rotary motion of the electric motor into reciprocating motion of a punch generally designated 16, the latter being operatively mounted in the nose 12.

The nose 12 is a cylindrical part that is provided with an external flange 17 which is located intermediate the opposite ends thereof. One end portion of the nose 12 is projected into the head 11 from the underside of the latter, and the nose 12 is secured to the head 11 through the medium of the flange 17. The lower terminal portion of the nose 12 is tapered to a blunt tip, as indicated in Figure 2. The nose 12 is provided with a central through bore that has an upper section designated 18 and a lower communicating section of reduced diameter designated 19.

The punch 16 is made from bar stock that is uniform and round in transverse section. This bar stock is cut away on diametrically opposite sides to thereby render the lower end portion thereof generally rectangular in transverse section, and to thereby form a flat blade 243 the broad sides of which respectively face fore and aft of the tool. The round bar stock is additionally cut away on one side to thereby flatten the punch shank, designated 21, on the forwardly facing side thereof, as at 22. This flattened surface 22 extends longitudinally the full length of the shank and is of a width substantially smaller than the diameter of the bar stock.

A lower end portion ofthe punch 16 is slidably received in the reduced diameter bore 19 of the nose part 12 for guidance thereby. For guiding the punch blade 26, the nibbler tool is provided with a guide 23 of generally T-shape in vertical transverse section suitably fitted into and secured to the back of the nosepart l2, and with a die plate 24 that is carried by the guide 23. In addition, the tool is provided with a stripper member 25 that is suitably fitted into the lower terminal portion of the nose part 12. If desired, reference may be had to applicants copendiug application, Serial No. 583,181, filed May 7, 1956, for a more detailed description of the guide member 23, die plate 24 and stripper 25, and for a more detailed description of the manner of the assembly thereof with the nose part 12 and punch 16.

The means aforesaid for translating rotary motion of the electric motor into reciprocating motion of the punch 16 comprises a generally cylindrical plunger or ram 2-6 that is provided with a main body part 27 which terminates at its upper end in a head part 28 of enlarged diameter and flattened on the fore and aft sides thereof to provide a pair of parallel surfaces, respectively designated 29 and 30, spaced apart'a distance corresponding to the diameter of the main body part 27.

Referring particularly to Figure 2, the ram 26 is generally of T-shape in longitudinal section, the stem or main body part 27 being slidably fitted into, and the head part 23 being disposed in superposed spaced relation to the upper end portion of the nose part 12. Extending transversely through the head part 28 is a rectangular opening 31 that is defined by horizontally extending upper and lower walls designated respectively 32 and 33 and vertically extending opposite end walls designated respectively 34 and 35.

Extending through the ram 26 is a central bore that has upper, intermediate and lower sections designated respectively 36, 37 and 38. These bore sections are of successively decreasing'diameter, and the intermediate section 37 is internally threaded. The larger diameter bore section 36 communicates, intermediate the opposite ends thereof, with the rectangular opening 31.

The punch shank 21 slidably projects upwardly through the lower bore section 38 and freely into the intermediate bore section 37. Threaded into the latter bore is a set screw 39 that abuts the upper end of the punch shank 21 for backing up the punch 16 during the working stroke thereof. Threaded through the wall of the ram 26, on the fore side thereof, and projecting respectively into the lower and intermediate bore sections for engaging the flat surface 22 of the punch shank 21 are a pair of set screws 40 and 41 operative to secure the punch 16 against displacement from the ram 26 during the non-working stroke thereof.

The head 11 of the tool is provided with a hollow casing section that has on the underside thereof a wall 42. The upper end portion of the nose 12 is projected through, and the flange 17 is secured to this wall, 42. Integral with the latter are upright transversely extendingfore and aft walls, designated respectively 43 and 44, and longitudinally extending opposite side walls designated respectively 45 and 46. The top of this casing section is prothe electric motor into reciprocating motion of'the punch '16 additionally comprises a pair of ball bearing units, designated 494, respectively mounted in the transversely extending casing walls 43 and 44. Journalled in these units are concentric opposite end portions,--respectively designated 50 and 51, of a shaft that is projected through the ram head 28. The intermediate portion of the shaft aforesaid, designated 52, is eccentricaliy disposed relative to the opposite end shaft portions 59 and 51 and is revolubly extended through a central aperture 53 formed in a slide block 54, which latter is mounted in the head 23 for shifting movement from side to side within the rectangular opening 31. The shaft portion 51 is operatively connected with the electric motor through the medium of a gear train designated generally by'the numeral 55. '3 1 In the operation of the tool, the eccentric shaft rotates in the concentric bearing units 4949, about its principal axis, and the intermediate eccentric shaft portion 52 rotates therewith for reciprocating as a unit the assembly including the slide block 54, ram 26 and p unch 16. It will bc observed that the eccentric shaft is adequately supported at both ends thereof in the bearing units 49-49 mounted respectively in the casing walls 43 and 44 on opposite sides of the ram head 28. a

The intermediate eccentric shaft portion 52v is provided with a transversely extending access opening designated 56, the fore end of the shaft is slotted treat 57, and the transversely extending fore Wall 43 of the casing is provided with an access opening 58 and a removable closure member 59. In addition, the slider block 54 is provided with an access opening normal to the central aperture 53, which access opening, designated 66, communicates intermediate the opposite ends thereof with the central aperture 53. a v

In order to remove the punch 16 for resharpening, or for any other purpose, the closure members 48 and 59 are removed and a suitable tooi is inserted through the access opening 58 for insertion into the slot 57 that is formed in the exposed end of the eccentric shaft. Then the eccentric shaft is turned to align the access opening 56 that is formed therein with the access opening 61) that is formed in the sliderblock and the central through bore that is formed in the ram 26. inserted through the access openings 47, 56 and 64) and into the central through'bore sections 36 and 37 for loosening andremoving the set screw 3?. Now asuitable tool is inserted through access openings 61 and 62, fo1rned respectively in the fore wall 43 of thecasing and the wall of the nose part 12, for turning out the se t' screws 40 and 41 slightly to complete release of the punch 16, which latter is thereby freed for removal thereof through the ram 26 and the access openings 60, 56 and 47; "The steps in the operation of replacing a resharpened punch are essentially the same as just described, but they-are reversed in order.

It will be observed that the construction of the present invention greatly facilitates removal and replacement of the punch 16. t I a s It will be understood, of course, thatthe present invention is susceptible of various changes and modifications which may be made from time to time without departing from the general principles or real spirit thereof, and his intended to claim the same broadly, as wellasspecifically, as indicated by the appended claims. What is claimed .as new and useful is: g 7

l. A motor-driven sheet metalcutting'tool comprising an elongated casing adapted'to be hand held including a head section having opposed'wall' areas, a ramreciprocally mounted between said'opposed wall areas. and having a central through bore; a punch projected freely into one end ofsaidcentral here, an element threaded into the Then a suitable tool is.

opposite end of said central bore and backing up said punch, and means operatively intervening said motor drive and ram for reciprocating said ram and punch, said means including a shaft projected transversely through said ram and having longitudinally spaced portions on opposite sides of said ram respectively journalled in said opposed casing wall areas, said shaft being provided with a transversely extending opening and being movable about its principal axis for axial alignment of said shaft opening with said ram bore for access to said punch backing element through said ram bore and shaft opening.

2. A motor-driven sheet metal cutting tool comprising an elongated casing adapted to be hand held including a head section having opposed wall areas, a ram reciprocably mounted between'said opposed wall areas and having a central through bore, a punch projected freely into one end of said central here, an element threaded into the opposite end of said central bore and backing up said punch, and means operatively intervening said motor drive and ram for reciprocating said ramand punch, said means including an element fixed axially of said ram and mounted by the latter for shifting movement transversely thereof, an eccentric shaft projected through the element aforesaid and having longitudinally spaced portions on opposite sides of said ram respectively journalled in said opposed casing wall areas,'the element and shaft aforesaid being provided with through openings, and said shaft being movable about its principal axis for shifting said element and for axial alignment of the through openings in said element and shaft with the through opening in said ram for access to said punch backing element through said aligned openings. 7

3. A motor-driven sheet metal cutting tool comprising an elongated casing adapted to be hand held including a head section having opposed wall areas and an access opening between the latter, a ram reciprocably mounted between said opposed wall areas and having a'central through bore underlying the access opening aforesaid, a punch projected freely into one endof said central bore, an element threaded into the opposite end of said central bore and backing up said punch, and means operatively intervening said motor drive and ram for reciprocating said ram and punch, said means including a block fixed axially of said ram and slidably mounted by the latter for rectilinear shifting movement transversely thereof, an eccentric shaft projected through the block aforesaid and having longitudinally/spaced portions on opposite sides of said ram respectively journalled in said opposed casing wall areas, the block and shaft aforesaid being provided with through openings, and said shaft being movable about its principal axis for shifting said block and for axial alignment of the through'openings in said block and shaft with the through opening in said ram for access to said punch backing part through the access opening formed in said casing and the openings aligned in the manner aforesaid.

4. A motor-driven sheet metal cutting tool comprising an elongated casing adapted to be hand held including a head section having opposed wall areas, a ram reciprocably mounted between said opposed wall areas and having a central through bore, a punch projected freely into one end of said central bore, an element threaded into the opposite end of said central bore and backing up said punch, and means operatively intervening said motor drive and ram for reciprocating said ram and punch, said means including a shaft projected transversely through said ram and having longitudinally spaced portions on opposite sides of said ram respectively journalled in said opposed casing wall areas, said shaft being provided with a transversely extending opening and being movable about its principal axis for axial alignment of said shaft opening with said ram borefor access to said punch backing element through said ram bore' and shaft opening, one end of said shaft being provided with means for facilitating movement of said shaft to align said shaft opening and ram bore in the manner aforesaid, and the associated one of the Wall areas aforesaid being provided with an opening for direct access to said shaft moving means.

5. A motor-driven sheet metal cutting tool comprising an elongated casing adapted to be hand held including a head section having opposed wall areas, a tubular guide extending into said casing between the opposed wall areas aforesaid, a ram reciprocable in said guide and having a through bore, a punch projected freely into one end of said central bore, an element threaded into the opposite end of said central bore and backing up said punch, means threaded into the side of said ram and frictionally engaging said punch for securing the same against axial displacement, and means operatively intervening said motor drive and ram for reciprocating said ram and punch, said means including a shaft projected transversely through said ram and having longitudinally spaced portions on opposite sides of said ram respectively journalled in said opposed casing Wall areas, said shaft being provided with a tranversely extending opening and being movable about its principal axis for axial alignment of said shaft opening with said ram bore for access to said punch backing element through said ram bore and shaft opening, and for simultaneously aligning said punch securing means With aligned access openings formed in said casing and guide members.

References Cited in the file of this patent UNITED STATES PATENTS 2,318,982 Wilhide May 11, 1943 2,631,370 Gray Mar. 17, 1953 2,750,667 Johnson June 19, 1956 

